GUARANTEES AND COMMITMENTS - Credit Commitments and Lines of Credit (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Guarantor Obligations
Credit commitments	$ 1,016,113	$ 1,015,564
Unsettled reverse repurchase and securities borrowing agreements	138,000	111,600
Unsettled repurchase and securities lending agreements	75,500	37,300
Commercial and similar letters of credit
Guarantor Obligations
Credit commitments	5,996	5,316
One- to four-family residential mortgages
Guarantor Obligations
Credit commitments	2,379	2,394
Revolving open-end loans secured by one- to four-family residential properties
Guarantor Obligations
Credit commitments	6,458	6,380
Commercial real estate, construction and land development
Guarantor Obligations
Credit commitments	14,154	15,170
Credit card lines
Guarantor Obligations
Credit commitments	688,339	683,232
Commercial and other consumer loan commitments
Guarantor Obligations
Credit commitments	293,297	297,399
Other commitments and contingencies
Guarantor Obligations
Credit commitments	5,490	$ 5,673
UNITED STATES
Guarantor Obligations
Credit commitments	825,030
UNITED STATES | Commercial and similar letters of credit
Guarantor Obligations
Credit commitments	663
UNITED STATES | One- to four-family residential mortgages
Guarantor Obligations
Credit commitments	1,200
UNITED STATES | Revolving open-end loans secured by one- to four-family residential properties
Guarantor Obligations
Credit commitments	5,772
UNITED STATES | Commercial real estate, construction and land development
Guarantor Obligations
Credit commitments	12,552
UNITED STATES | Credit card lines
Guarantor Obligations
Credit commitments	612,236
UNITED STATES | Commercial and other consumer loan commitments
Guarantor Obligations
Credit commitments	187,295
UNITED STATES | Other commitments and contingencies
Guarantor Obligations
Credit commitments	5,312
In offices outside North America
Guarantor Obligations
Credit commitments	191,083
In offices outside North America | Commercial and similar letters of credit
Guarantor Obligations
Credit commitments	5,333
In offices outside North America | One- to four-family residential mortgages
Guarantor Obligations
Credit commitments	1,179
In offices outside North America | Revolving open-end loans secured by one- to four-family residential properties
Guarantor Obligations
Credit commitments	686
In offices outside North America | Commercial real estate, construction and land development
Guarantor Obligations
Credit commitments	1,602
In offices outside North America | Credit card lines
Guarantor Obligations
Credit commitments	76,103
In offices outside North America | Commercial and other consumer loan commitments
Guarantor Obligations
Credit commitments	106,002
In offices outside North America | Other commitments and contingencies
Guarantor Obligations
Credit commitments	$ 178